I sent a grand Seiko to Seiko UK to service in 2018 and when it came back it had more dust on the dial than Lord Asriel would know what to do with.
The watch had a poor PR so I sent it to them under warranty. It came back working ok then suddenly got worse, when I had a closer look they had left a huge fingerprint on the rotor as well. I sent it off to Duncan and the oils in the watch had dried up causing the problem (A lot of these watches had been sitting around for ages before sale). Duncan stripped the movement and cleaned it and I have not had a problem since (several years now). Basically all Seiko did was regulate it (without bothering to use gloves) and not check to see what the actual problem was.
My initial thought were also that Seiko UK were very good. Email respond they have the watch, login details to see the progress of the repair but now knowing what I do I wouldn’t trust them.